Gesture recognition has many advantages over other input means, such as the keyboard, mouse, speech recognition, and touch screen. The keyboard is a very open ended input device and assumes that the user has at least a basic typing proficiency. The keyboard and mouse both contain moving parts. Therefore, extended use will lead to decreased performance as the device wears down. The keyboard, mouse, and touch screen all need direct physical contact between the user and the input device, which could cause the system performance to degrade as these contacts are exposed to the environment. Furthermore, there is the potential for abuse and damage from vandalism to any tactile interface which is exposed to the public.
Tactile interfaces can also lead hygiene problems, in that the system may become unsanitary or unattractive to users, or performance may suffer. These effects would greatly diminish the usefulness of systems designed to target a wide range of users, such as advertising kiosks open to the general public. This cleanliness issue is very important for the touch screen, where the input device and the display are the same device. Therefore, when the input device is soiled, the effectiveness of the input and display decreases. Speech recognition is very limited in a noisy environment, such as sports arenas, convention halls, or even city streets. Speech recognition is also of limited use in situations where silence is crucial, such as certain military missions or library card catalog rooms.
Gesture recognition systems do not suffer from the problems listed above. There are no moving parts, so device wear is not an issue. Cameras, used to detect features for gesture recognition, can easily be built to withstand the elements and stress, and can also be made very small and used in a wider variety of locations. In a gesture system, there is no direct contact between the user and the device, so there is no hygiene problem. The gesture system requires no sound to be made or detected, so background noise level is not a factor. A gesture recognition system can control a number of devices through the implementation of a set of intuitive gestures. The gestures recognized by the system would be designed to be those that seem natural to users, thereby decreasing the learning time required. The system can also provide users with symbol pictures of useful gestures similar to those normally used in American Sign Language books. Simple tests can then be used to determine what gestures are truly intuitive for any given application.
For certain types of devices, gesture inputs are the more practical and intuitive choice. For example, when controlling a mobile robot, basic commands such as “come here”, “go there”, “increase speed”, “decrease speed” would be most efficiently expressed in the form of gestures. Certain environments gain a practical benefit from using gestures. For example, certain military operations have situations where keyboards would be awkward to carry, or where silence is essential to mission success. In such situations, gestures might be the most effective and safe form of input.
A system using gesture recognition would be ideal as input devices for self-service machines (SSMs) such as public information kiosks and ticket dispensers. SSMs are rugged and secure cases approximately the size of a phone booth that contain a number of computer peripheral technologies to collect and dispense information and services. A typical SSM system includes a processor, input device(s) (including those listed above), and video display. Many SSMs also contain a magnetic card reader, image/document scanner, and printer/form dispenser. The SSM system may or may not be connected to a host system or even the Internet.
The purpose of SSMs is to provide information without the traditional constraints of traveling to the source of information and being frustrated by limited manned office hours or to dispense objects. One SSM can host several different applications providing access to a number of information/service providers. Eventually, SSMs could be the solution for providing access to the information contained on the World Wide Web to the majority of a population which currently has no means of accessing the Internet.
SSMs are based on PC technology and have a great deal of flexibility in gathering and providing information. In the next two years SSMs can be expected to follow the technology and price trends of PC's. As processors become faster and storage becomes cheaper, the capabilities of SSMs will also increase.
Currently SSMs are being used by corporations, governments, and colleges. Corporations use them for many purposes, such as displaying advertising (e.g. previews for a new movie), selling products (e.g. movie tickets and refreshments), and providing in-store directories. SSMs are deployed performing a variety of functions for federal, state, and municipal governments. These include providing motor vehicle registration, gift registries, employment information, near-real time traffic data, information about available services, and tourism/special event information. Colleges use SSMs to display information about courses and campus life, including maps of the campus.